[BUG] Cowork "Virtual Machine Platform not available" — yukonSilver unsupported loop on Windows 11 Home, AMD Ryzen 7 5700U

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Cowork displays "Virtual Machine Platform not available" on every launch. Claude Desktop is classifying the VM configuration as yukonSilver not supported (status=unsupported) and looping through a delete/reinstall cycle, preventing the VM from ever initializing. This occurs despite all virtualization features being enabled and verified.
Notably, Cowork worked previously on the same Windows 11 Home edition on a prior device, confirming this is a regression in platform detection logic, not a system configuration issue.

Environment

Claude Desktop: v1.1.6041
OS: Windows 11 Home, Version 25H2, Build 26200.8037
CPU: 12th Gen Intel Core i5-12450H (per system-info.txt) — Task Manager confirms Virtualization: Enabled
RAM: 31.7 GB
Install type: MSIX
Virtual Machine Platform: ✅ Enabled
Windows Hypervisor Platform: ✅ Enabled

Log evidence (%APPDATA%\Claude\logs\cowork_vm_node.log):
2026-03-13 11:46:59 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported)
2026-03-14 06:36:40 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported)
2026-03-28 11:32:03 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported)
The vm_bundles folder does not exist — the VM never initializes. On 3/12/2026 the VM briefly downloaded successfully (rootfs.vhdx, vmlinuz, initrd all confirmed, Network: CONNECTED, API: REACHABLE) before being deleted after a restart/update.
Related issues: #27397, #32004, #25136, #29887

What Should Happen?

Cowork detects virtualization is enabled and initializes the VM workspace successfully.

Error Messages/Logs

Steps to Reproduce

Install Claude Desktop v1.1.6041 on Windows 11 Home (Build 26200.8037) via MSIX
Enable Virtual Machine Platform and Windows Hypervisor Platform in Windows Features
Restart computer
Launch Claude Desktop and navigate to the Cowork tab
Observe "Virtual Machine Platform not available" error
Check %APPDATA%\Claude\logs\cowork_vm_node.log — only yukonSilver not supported (status=unsupported) entries present on every launch
Check %APPDATA%\Claude\vm_bundles — folder does not exist, VM never initializes

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Version 1.1.9310 (cb30ac)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

Despite already enabling VMP, Claude Cowork does not detect it.

<img width="1920" height="1080" alt="Image" src="https://github.com/user-attachments/assets/354fb50d-97fe-405f-ba41-8a8906b457df" />